Photoelectric monolithic integration of PIN detector and transimpedance amplifier

A silicon-based PIN detector was designed, which had large area and high response, the surface area of the PIN detector was 4.1 mm×13.8 mm, and the thickness was about 420 μm. The ring-shaped Al electrode was used to extract the photocurrent signal in the photosensitive surface of the PIN detector. The test was performed under a constant laser light source with a wavelength of 860 nm, and its responsivitywas 0.6 A/W. Next, a new feasibility method for photoelectric monolithic integration was proposed, that is, by using the intrinsic I layer area of ​​the non-illuminated area of ​​the PIN detector, a transimpedance amplifier compatible with the structure and process of the PIN detector was designed, the photoelectric monolithic integration of the PIN detector and the transimpedance amplifier was realized on the premise that the structure and performance of the PIN detector had not changed. Finally, under the actual pulsed laser signal with a wavelength of 860 nm, a pulse width of 100 ns, and a working frequency of 10 kHz, the pulse response of the successful tape-out PIN detector and the photoelectric monolithic integrated chip was compared and tested. The results show that the pulse voltage signal of the photoelectric monolithic integrated chip is amplified by 1000 times compared with the pulse photocurrent signal of the PIN detector, while the pulse width is basically unchanged, the amplification factor is consistent with the theoretical transimpedance value of 1000 Ω. The integrated photoelectric chip is used in the laser receiving module of the laser fuze system. Through photoelectric monolithic integration, the signal-to-noise ratio of the output signal on the PIN detector can be improved, and the stability of the system can be enhanced, it can also meet the needs of the miniaturization of the laser fuze system.